Over the last decade or so, many commercial and governmental entities have installed communication networks in order to allow their employees access various network resources. To improve efficiency and to support mobility, many wireless access enhancements have been added to local, personal, and wide area networks. Based on these enhancements, Wireless Local Area Networks (WLANs), Personal Area Networks (PANs) and Wide Area Networks (WANs) have been and continue to be utilized by more and more users.
For instance, a WLAN supports communications between a number of wireless devices without any required line of sight between devices. In current network configurations, multiple Access Points (APs) are connected to a wired network, such as an Ethernet network for example, and each AP operates as a relay station by supporting communications between resources of the wired network and wireless stations (STAs). STAs are fixed or mobile wireless devices, where the mobile devices enable users to alter their physical locations, but still communicate over the network.
In accordance with many WLAN transmission schemes, including transmission schemes operating in accordance with any Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, each wireless device communicates with another device over a wireless channel. The resources for each wireless channel, that directly affect the Quality of Service (QoS), may be allocated according to any number of resource management mechanisms that can be broadly classified as shaping or policing. “Shaping” involves temporary storage or queuing of packets received in excess of a pre-negotiated or pre-configured limit for a particular wireless channel while “policing” involves dropping of packets exceeding the pre-negotiated or pre-configured limit for that wireless channel. A combination of policing and shaping may also be used.
One of the key differences between wireless and some wired networks is that the capacity of a wireless channel is dynamic and varies based on many factors. For instance, in a 100 Mbps (megabit per second) switched Ethernet network supporting ten (10) data transmissions flows, each flow may be allocated approximately 10 Mbps (less any overhead) since the (bandwidth) capacity for wired Ethernet medium is fairly static. For a wireless channel within a wireless medium, however, the available capacity from the wireless transmitter's perspective varies over time based on a variety of factors such as traffic between other devices on the same channel; interference on the wireless channel; number of retries required per transmission; the modulation and coding used for communication with a receiver; transmit-to-receive ratio; and media access delays and channel access overhead depending on the number of active devices if Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) is used.
Hence, it would be advantageous to develop a scheme that more accurately and dynamically estimates available capacity for one or more wireless channels or streams and takes into account implementation constraints that adversely influence capacity estimation and proportional sharing of capacity of the wireless channel(s) or stream(s) within a channel.